07389817 is referenced by 16 patents and cites 24 patents.

A riser control device, particularly designed to be used in connection with spool or horizontal production trees (12) for wells in sub-sea oil and gas installations. Within a housing (1,2) of the device is provided, in opposed direction, radially movable pair of rams (6) for isolating (sealing off) the well and simultaniously, in opposed direction a radially movable pair of shear blades (7) for cutting off an intervention string or the like. The rams (6) and blades (7) are driven by means of a vertically disposed actuator (8,9,23) integrated in the housing (1, 2). The actuator may be in the form of a hydralically driven annular piston (23)/annular chamber (29,30) device, which via piston rods (14) and translation beams (8) transforms the movement of the piston (23) to open or close the rams (6) and shear blades (7).

Title
Riser control device
Application Number
10/501325
Publication Number
7389817 (B2)
Application Date
January 15, 2003
Publication Date
June 24, 2008
Inventor
Jeffrey Charles Edwards
Suffolk
GB
Per Almdahl
Oslo
NO
Agent
Wenderoth Lind & Ponack L
Assignee
Norsk Hydro ASA
NO
IPC
E21B 29/12
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